I don't know if it's the best place, but I would like to point out (I'm quite sure that it was brought up a while ago), that links to aptosid.list and debian.list in the en manual (http://aptosid.com/manual/en/sys-admin-apt-en.htm#apt-cook) are dead end

Code:

Not Found

The requested URL /files/misc/sources.list.d/aptosid.list was not found on this server.
Apache/2.2.22 (Debian) Server at aptosid.com Port 80

Luckily list of different mirros is available also in the Download/Mirrors section